An SM420 has a rectangular plate held on by a handful of bolts on the driver's side of the transmission for a pto (power take off).

Reverse is all the way to the left, and then back. The stick should move easily between the 1-2 and 3-4 slots, and require a bit more force to come further left for reverse.

Post a picture. They aren't hard to recognize.


1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble...